Fuel gas composition

ABSTRACT

A fuel gas composition which comprises essentially a mixture gas of 65-90 volume percent of acetylene and 35-10 volume percent of LP gas, the mixture of gas being dispersed in a high pressure container which is packed with a porous material permeated with a solvent or solvents selected from a group consisting of acetone, toluene and xylene. The composition is found to be safely storable, transportable and usable under high pressure, has relatively constant composition upon withdrawal from storage, and effective in welding or torch cutting.

Maruyama et al.

Jan. 30, 1973 FUEL GAS COMPOSITION Inventors: Takeji Maruyama, Nishinomiyashi;

Assignee:

Filed:

Appl.

Tadao Uenae, Osakashi, both of Japan lwatani & Co., Ltd., Osaka, Japan Jan. 13, 1969 Nol: 790,847

Foreign Application Priority Data June 3,1968- May4, 1968 Japan .L..43/38l I5 Japan ..43/29962 Field of Search ..44/52; 48/197 FM References Cited UNITED STATES PATENTS 2/1922 Schreiber ..44/52 1,528,765 3/1925 Harris ..44/52 l,863,50l 6/l932 Roffey ..44/52 2,626,459 l/I953 Viles 48/197 FM Primary Examiner-Daniel E. Wyman Assistant Examiner-Mrs. Y. H. Smith Attorney-Arthur Schwartz [57] ABSTRACT A fuel gas composition which comprises essentially a mixture gas of 65-90 volume percent of acetylene and 35-10 volume percent of LP gas, the mixture of gas being dispersed in a high pressure container which is packed with a porous material permeated with a solvent or solvents selected from a group consisting of acetone, toluene and xylene. The composition is found to be safely storable, transportable and usable under high pressure, has relatively constant composition upon withdrawal from storage, and effective in welding or torch cutting.

5 Claims, N0 Drawings FUEL GAS COMPOSITION This invention relates to a composition of matter useful as a fuel gas, and more particularly to a composition which is storable, transportable and usable safely under high pressure, has relatively constant composition upon withdrawal from storage, and is particularly effective in welding or torch cutting operations.

Acetylene gas is the most preferable fuel gas used in welding or flamecutting operations, because desirable high temperature of about 3,000-3,500C is easily obtained by burning it in the presence of oxygen. However, acetylene gas is very explosive in a vast range of concentrations (about 2.5-8l volume percent in air), and further easily calorificates by its decomposition reaction to carbon and hydrogen under a condition of high temperature and high pressure and the calorification reaction causes the explosion. Therefore, the employment of acetylene gas as a fuel gas involves considerable risks in the storage, working or transportation. in order to avoid these risks, it is well known that acetylene gas is used in a form of dispersing it in a packing medium to stabilize it. But, in such a type, it is restored to the original dangerous conditions when acetylene gas is withdrawn from the packing. Furthermore, when any shocks (e.g., impact, heating, etc.) are given to the packing during the working, storing or transporting period, the explosion of the gas is likely to occur. Thus, the security of acetylene gas is insufficient in the any hitherto known stabilized form for said gas.

Although attempts were made to overcome the foregoing difficulties and other disadvantages, none, as far as we are aware, was entirely successful when carried into practice commercially on an industrial scale.

It has now been discovered that the fuel gas composition, which comprises a mixture of acetylene and LP gas in a specific ratio and said mixture gas is dispersed in a high pressure container packed with a porous material permeated with a solvent, is non-explosive and therefore very safe as a fuel 'gas when compared with acetylene gas. Furthermore, it has been found that the mixture gas may be withdrawn in a constant concentration of its components, which make it possible to obtain a constant flame temperature. The flame temperature is found also percent up compared with acetylene gas and therefore, the working efficiency of the mixture gas increases l0 percent up compared with acetylene gas.

it is an object of the present invention to provide a safe gas composition in its application, transportation and storage.

Another object of the present invention is to provide a fuel gas composition which may be withdrawn in a constant concentration of the component gases.

The invention also contemplates providing a fuel gas composition which can offer a high and constant temperature flame, and cut faster than acetylene.

It is also the purpose of the invention to provide a low cost fuel gas composition.

Other objects and advantages will become apparent from the following description.

The mixture gas of the present invention consists essentially ofa mixture of from about 65 to about 90 percent of acetylene and from about 35 to about 10 percent of LP gas. The LP gas is selected from a group consisting of propylene, propane and butane, and a mixture thereof. Preferred purity of the acetylene is more than 99 percent and the LP gas is desirably more shown in Examples 3 and 5. When more than percent of acetylene is present, the explosive property of acetylene affects seriously the mixture gas (See; Example 2 The porous material employed in the present fuel gas composition means the material having numerous holes or clinks wherein the solvent is absorbed, and exemplified as follows; charcoal, calcium silicate, silica gel, cellulose, porous fused alumina, felt, rock wool, diatomaceous earth, etc.

These porous materials are permeated with a solvent or solvents selected from a group consisting from acetone, xylene and toluene. The explosion limit of acetone in air is 2.55-l2.8 percent, xylene is 1.0-6.0 percent and toluene 1.27-6.75 percent. The flash point of acetone is -l7.8 C, xylene is 27' C and toluene is 4.4 percent. Boiling point of acetone is 56 C, xylene is about 140 C and toluene is 110 C. These properties contribute to the safety, efficiency, flame temperature and workings of the present fuel gas composition. Preferably, the container (which may be constructed of any one of a great number of suitable materials, such as, for example, steel) is charged with the porous material in an amountsubstantially 100 percent by volume. A conventional method for effecting the above aim would be to charge the container with an aqueous emulsion of, e.g., calcium silicate. Upon evaporation of the water there is created a sponge-like structure within the container, with the voids of such porous material constituting from about 90 to percent of the gross volume thereof.

The fuel gas composition of the present invention is very stable, since the explosion limit of it is extremely suppressed in comparison with that of acetylene as shown in Example 2. For example, the explosion limit of the mixture gas of acetylene 70 percent and propylene 30 percent is decreased to 5 kg/cm abs, and that of the mixture gas of acetylene 65 percent and propylene 35 percent is decreased 6 kg/cm abs, while that of acetylene percent is 1.4 kg/cm abs. Thus, by employing our fuel gas composition, it is realized to avoid the explosion caused by the presence of acetylene. Further, the LP gas which is another component of the present fuel composition, works effectively as a fuel gas in differing from the inactive gases which is usually employed as diluent gas for acetylene.

Prior experience has shown that the compositions of both the gas and the liquid phases stored in a container under pressure vary as gas is withdrawn. A relatively constant gas phase composition is desirable to provide a constant flame temperature in order that welding, cutting, or the like techniques may be conducted over the full period of gas withdrawal from the storage container. Present fuel gas composition is best suited for such purpose, because it has not only a relatively constant composition upon withdrawal from storage, but also is superior to acetylene in non-explosive property, non-back firing property, high temperature, working efficiency, cost, etc.

The solubility of the gas mixture to the solvents and the cubical expansion of the solvents caused by absorption of the gas mixture are practically the same as that of acetylene. Therefore, when the present gas mixture EXAMPLE 2.

The explosion limit of the mixture gas of acetylene and propylene is shown in the Table 2. it is apparent from the Table that the gas mixture is very stable since is absorbed under pressure in the high pressure con- I d d tainer, the safety space should be constructed as same g extreme y Suppresse compare as that of acetylene gas container. 1 that 0 Met) ene in use, the fuel gas composition of the present inven- Table tion may be handled in almost the same manner as conventional gases. Explosion Limit Preferably, the pressure within the container, which C l f f T ta! P ofth 011C611 I8 1011 O O I'fiSSlll'C C 1s dependent upon ambient temperatures and the acetylene gas womb) mixture 838 (kg/CW3) amount of fuel gas to be confined therein, falls within 100 1. the range of from about 5 kg/cm to about 30 kg/cm. 3%

Even more preferably, it is about 11 kg/cm at an am- 15 70 4.8 bient temperature of about 10 C; 13 kg/cm at about 23 8 1 C; 17 kg/cm at about 30 C; and 20 kg/cm at V about Various gas mixture compositions of acetylene and l gh f Present "Wentlon h beel'ldfascl'lbed 20 propylene are stored into the container (31) in the same COlljUl'lCtlOIl w1th preferred embodiments, 1t 15 to be unmanner as in Example 1 The, while the mixture gas defstood that modifications and Variations y be compositions are withdrawn from the container in the resorted to without departing from the spirit and scope r f 0,2 in /h r and r leasin pressure 0.2 kg/cm of the invention, as those skilled in the art will readily th inner p sure of the container and gas components understand. Such modifications and variations are conare measured throughout the withdrawing period. The sidered to be within the purview and scope of the inresults are listed in the following table 3.

TABLE 3 [Propylene gas molar percent in the Withdrawn gas] Mixture gas compositions (molar percent) Inner pressure of container (kgJem. gauge) Remarks, 0111102111 1011987654 3210 c.

14 86 12 13.8 14 14 14 14 14 14 14 14 14 14 16-18 23 72 24 26 27 2s 2s 2s 2s 2s 2s 2s 2s 2s 13 as e5 30 32.5 34 34.11 as 35 25 as as as as as 13 40.5".-. 53.5 33 37 40 42.5 43.5 44 45 45 44.5 44 43 40 16 vention a nd appended claims. Example 1. EXAMPLE 4.

Acetylene gas and propylene gas are mixed to obtain A mi t I f l 0 various gas mixtures thereof, which mixtures contain Gem :2 iisg g b 19 225"; acetylene gas in the range of 53.5-100 percent and p g can I up m d pressure container (capac1ty: 31) wh1ch is packed w1th propylene gas 1n 14-100 percent. In a high pressure 45 calc1um s|11cate and permeated With 11 of toluene or contamer, a porous material (charcoal mass) 1s packed xylene. The f1ll1ng up 1s conducted under pressure of and then 1 l of acetone 1s permeated. While coolmg the 2 container b di in in 8 water bath of l6 18 C the 1.5 kg/cm abs at the rate of 450l/hour (calculated as a y PP 8 1 volume under the atmospheric pressure), while cooling mixed gases are filled up therem under pressure of 1.5 h o k K abs at the rate of OI/hour (calculated as a t e contamer at 16-18 C. Table 4 1s the comparative 8] d th t h I d th data of the dissolution velocity of the mixture gas and m 8 a mosp Pressure e the pressure rise with the commercial acetylene gas dissolutlon velocity of the gas mixtures and the pressure Solved in acetone rise are measured. The results are shown in the following table 1 as compared with the values of acetylene T bl 4 gas.

Pressure (kg/cm MQauge lxture as 1 hour 2 h 3 h A W *7 {M o s s Solvent ours ours A 1 4.5 Table 1 12.0 28.0 x313? 5.3 3.3 ii 7.0 28.0 Toluene 5.2 8.8 11.0 Pressure (kg/cm Gauge) gilxltug'glssH 1 hour 2 hours 3 hours I I 5 z$6109 O 92 2 EXAMPLE 5. 1- 2:; 3:? Hg Propylene gas concentration (molar percent) is mea- 5 45 sured 1n the same manner as in Example 3. The result is 0 5.5 7.6 8.6 shown in the following Table 5.

TABLE Mixture gas composition Rema rks, (molar percent) Inner pressure of container (kg/cm." gauge) 0.

Calls 02H; 11 1O 9 8 7 6 5 4 3 2 1 0 EXAMPLE 6 Having thus disclosed the invention, what is claimed The working properties of the fuel composition of ,Examples 1 and 4 are compared with the commercial acetylene gas 1. A pressurized fuel package for supplying a fuel gas mixture in substantially constant gas proportions com-' prising: a container packed with a porous material permeated with a solvent selected from the group consisting of acetone, xylene, toluene and mixtures thereof having absorbed therein a gaseous fuel composition consisting essentially of an admixture of from about 65 to volume percent acetylene gas and from about 35 to 10 volume percent of a gas selected from the group consisting of propylene, propane and butene,

2. The fuel package of claim 1 wherein the porous material is selected from the class consisting of charcoal, calcium silicate and silica gel.

3. The fuel package of claim 1 wherein the second gas is propylene.

4. The fuel package of claim 1 wherein the second gas is propane.

5. The fuel package of claim 1 wherein the pressure in the container is in the range of from about 5 kg.cm to about 30 kglcm 

1. A pressurized fuel package for supplying a fuel gas mixture in substantially constant gas proportions comprising: a container packed with a porous material permeated with a solvent selected from the group consisting of acetone, xylene, toluene and mixtures thereof having absorbed therein a gaseous fuel composition consisting essentially of an admixture of from about 65 to 90 volume percent acetylene gas and from about 35 to 10 volume percent of a gas selected from the group consisting of propylene, propane and butene.
 2. The fuel package of claim 1 wherein the porous material is selected from the class consisting of charcoal, calcium silicate and silica gel.
 3. The fuel package of claim 1 wherein the second gas is propylene.
 4. The fuel package of claim 1 wherein the second gas is propane. 